1.1 这些测试方法包括测定水蒸气通过油漆、清漆、油漆和其他有机涂层薄膜的速率。所述膜可以是游离膜，也可以应用于多孔基板。 1.2 一种类似但更普遍适用的测试方法是测试方法 E96 当涉及其他材料时，应考虑这一点。 1.3 测试方法中包括两种测试方法 D1653 具体如下: 1.3.1 试验方法A- 干杯法，以及 1.3.2 试验方法B- 湿（佩恩）杯法。 1.3.3 通过不同方法或测试条件获得的结果不应一致。应选择最接近使用条件的方法。 1.4 以英寸-磅为单位的数值应视为标准值。括号中给出的值是到国际单位制的数学转换，仅供参考，不被视为标准值。换算系数见 13.2.1.2 和 13.2.2.2 . 1.5 市场上有一些仪器声称比测试方法中描述的方法更容易、更快速地测量薄膜的水蒸气透过率 D1653 和 E96 . 它们基本上与ASTM方法中的测试类型相同，但使用的是仪器。然而，似乎没有进行并列测试，将使用此类仪器的测量结果与这些ASTM方法的精度和准确性进行比较。 1.6 本标准无意解决与其使用相关的安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.7 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 影响有机涂层性能的因素之一是其抵抗或帮助水蒸气通过的能力。在某些服务中，例如，外部木材和砌体，涂层必须允许适量的水蒸汽通过薄膜而不会损坏薄膜。因此，涂层的水蒸气传输特性对于评估其实际使用性能非常重要。 5.2 这些测试方法的目的是获得透过渗透性从高到低的涂层的水蒸汽传递值。这些值用于设计、制造和营销。 5.3 水蒸气透过率不是膜厚度、温度或相对湿度的线性函数。 5.4 只有在相同的严格控制的温度和相对湿度条件下测试涂层，并且其厚度相等时，才可以在涂层的相对额定值中使用水蒸气透过率（WVT）和水蒸气渗透率（WVP）的值。 5.5 试验方法A- 干杯法是获得与传统住宅相关的数值的首选测试方法，其中预计不会有高相对湿度。 5.6 试验方法B- 湿杯法是获得与阻隔材料附近预期具有较高相对湿度的应用相关值的首选试验方法。一般来说，涂层对水分的渗透性越强，这是许多可减水涂层的典型特征，当在高湿度中测试和暴露时，其对水的亲和力越大，透射率增加越大。吸水可能使涂层密度降低，从而使水分容易扩散，并导致比干燥环境中更高的水汽透过率（WVTR）。

1.1 These test methods cover the determination of the rate at which water vapor passes through films of paint, varnish, lacquer, and other organic coatings. The films may be free films or they may be applied to porous substrates. 1.2 A similar, but more generally applicable test method is Test Methods E96 which should be considered when other materials are involved. 1.3 Two test methods are covered in Test Methods D1653 as follows: 1.3.1 Test Method A— Dry Cup Method, and 1.3.2 Test Method B— Wet (Payne) Cup Method. 1.3.3 Agreement should not be expected between results obtained by different methods or test conditions. The method that most closely approaches the conditions of use should be selected. 1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. Factors for conversion are stated in 13.2.1.2 and 13.2.2.2 . 1.5 There are instruments on the market that purport to measure water vapor transmission of films more easily and rapidly than the methods described in Test Methods D1653 and E96 . They run essentially the same kinds of tests as in the ASTM methods, but do so instrumentally. However, it appears that no side-by-side tests have been run comparing results from measurements with such instruments to these ASTM methods for precision and accuracy. 1.6 This standard does not purport to address the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 One of the factors affecting the performance provided by an organic coating is its capability of resisting or aiding the passage of water vapor. In some services, for example, exterior wood and masonry, the coating has to allow moderate amounts of water vapor to pass through the film without damage to it. Hence, the water vapor transmission characteristics of coatings are important in assessing their performance in practical use. 5.2 The purpose of these test methods is to obtain values of water vapor transfer through coatings that range in permeability from high to low. These values are for use in design, manufacture, and marketing. 5.3 The water vapor transmission is not a linear function of film thickness, temperature or relative humidity. 5.4 Values of water vapor transmission rate (WVT) and water vapor permeance (WVP) can be used in the relative rating of coatings only if the coatings are tested under the same closely controlled conditions of temperature and relative humidity, and if their thicknesses are equal. 5.5 Test Method A— The Dry Cup Method is the preferred test method for obtaining values that relate to conventional dwellings where high relative humidities are not anticipated. 5.6 Test Method B— The Wet Cup Method is the preferred test method for obtaining values that relate to applications where high relative humidities are anticipated in the vicinity of the barrier material. In general, the more permeable a coating is to the passage of moisture as is typical of many water-reducible coatings, the greater its affinity for water and the greater the increase in transmission when tested in and exposed to high humidities. Absorption of water may make a coating less dense, thus allowing moisture to diffuse easily and cause a much higher moisture vapor transmission rate, (WVTR) than would occur in drier environments.